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<h1 class="title">treemodel.cpp 示例文件</h1>
<span class="subtitle">itemviews/simpletreemodel/treemodel.cpp</span>
<!-- $$$itemviews/simpletreemodel/treemodel.cpp-description -->
<div class="descr"> <a name="details"></a>
<pre class="cpp">

  <span class="comment">/****************************************************************************
  **
  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** Commercial License Usage
  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
  ** Software or, alternatively, in accordance with the terms contained in
  ** a written agreement between you and The Qt Company. For licensing terms
  ** and conditions see https://www.qt.io/terms-conditions. For further
  ** information use the contact form at https://www.qt.io/contact-us.
  **
  ** BSD License Usage
  ** Alternatively, you may use this file under the terms of the BSD license
  ** as follows:
  **
  ** &quot;Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
  ** met:
  **   * Redistributions of source code must retain the above copyright
  **     notice, this list of conditions and the following disclaimer.
  **   * Redistributions in binary form must reproduce the above copyright
  **     notice, this list of conditions and the following disclaimer in
  **     the documentation and/or other materials provided with the
  **     distribution.
  **   * Neither the name of The Qt Company Ltd nor the names of its
  **     contributors may be used to endorse or promote products derived
  **     from this software without specific prior written permission.
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  **
  ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  ** &quot;AS IS&quot; AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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  ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.&quot;
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/</span>

  <span class="comment">/*
      treemodel.cpp

      Provides a simple tree model to show how to create and use hierarchical
      models.
  */</span>

  <span class="preprocessor">#include &quot;treeitem.h&quot;</span>
  <span class="preprocessor">#include &quot;treemodel.h&quot;</span>

  <span class="preprocessor">#include &lt;QStringList&gt;</span>

  TreeModel<span class="operator">::</span>TreeModel(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> <span class="operator">&amp;</span>data<span class="operator">,</span> <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>parent)
      : <span class="type"><a href="../qtcore/qabstractitemmodel.html">QAbstractItemModel</a></span>(parent)
  {
      <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator">&lt;</span><span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span><span class="operator">&gt;</span> rootData;
      rootData <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;Title&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;Summary&quot;</span>;
      rootItem <span class="operator">=</span> <span class="keyword">new</span> TreeItem(rootData);
      setupModelData(data<span class="operator">.</span>split(<span class="type"><a href="../qtcore/qstring.html">QString</a></span>(<span class="string">&quot;\n&quot;</span>))<span class="operator">,</span> rootItem);
  }

  TreeModel<span class="operator">::</span><span class="operator">~</span>TreeModel()
  {
      <span class="keyword">delete</span> rootItem;
  }

  <span class="type">int</span> TreeModel<span class="operator">::</span>columnCount(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>parent) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (parent<span class="operator">.</span>isValid())
          <span class="keyword">return</span> <span class="keyword">static_cast</span><span class="operator">&lt;</span>TreeItem<span class="operator">*</span><span class="operator">&gt;</span>(parent<span class="operator">.</span>internalPointer())<span class="operator">-</span><span class="operator">&gt;</span>columnCount();
      <span class="keyword">else</span>
          <span class="keyword">return</span> rootItem<span class="operator">-</span><span class="operator">&gt;</span>columnCount();
  }

  <span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span> TreeModel<span class="operator">::</span>data(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>index<span class="operator">,</span> <span class="type">int</span> role) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (<span class="operator">!</span>index<span class="operator">.</span>isValid())
          <span class="keyword">return</span> <span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span>();

      <span class="keyword">if</span> (role <span class="operator">!</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>DisplayRole)
          <span class="keyword">return</span> <span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span>();

      TreeItem <span class="operator">*</span>item <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator">&lt;</span>TreeItem<span class="operator">*</span><span class="operator">&gt;</span>(index<span class="operator">.</span>internalPointer());

      <span class="keyword">return</span> item<span class="operator">-</span><span class="operator">&gt;</span>data(index<span class="operator">.</span>column());
  }

  <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>ItemFlags TreeModel<span class="operator">::</span>flags(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>index) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (<span class="operator">!</span>index<span class="operator">.</span>isValid())
          <span class="keyword">return</span> <span class="number">0</span>;

      <span class="keyword">return</span> <span class="type"><a href="../qtcore/qabstractitemmodel.html">QAbstractItemModel</a></span><span class="operator">::</span>flags(index);
  }

  <span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span> TreeModel<span class="operator">::</span>headerData(<span class="type">int</span> section<span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Orientation orientation<span class="operator">,</span>
                                 <span class="type">int</span> role) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (orientation <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>Horizontal <span class="operator">&amp;</span><span class="operator">&amp;</span> role <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>DisplayRole)
          <span class="keyword">return</span> rootItem<span class="operator">-</span><span class="operator">&gt;</span>data(section);

      <span class="keyword">return</span> <span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span>();
  }

  <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> TreeModel<span class="operator">::</span>index(<span class="type">int</span> row<span class="operator">,</span> <span class="type">int</span> column<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>parent)
              <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (<span class="operator">!</span>hasIndex(row<span class="operator">,</span> column<span class="operator">,</span> parent))
          <span class="keyword">return</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span>();

      TreeItem <span class="operator">*</span>parentItem;

      <span class="keyword">if</span> (<span class="operator">!</span>parent<span class="operator">.</span>isValid())
          parentItem <span class="operator">=</span> rootItem;
      <span class="keyword">else</span>
          parentItem <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator">&lt;</span>TreeItem<span class="operator">*</span><span class="operator">&gt;</span>(parent<span class="operator">.</span>internalPointer());

      TreeItem <span class="operator">*</span>childItem <span class="operator">=</span> parentItem<span class="operator">-</span><span class="operator">&gt;</span>child(row);
      <span class="keyword">if</span> (childItem)
          <span class="keyword">return</span> createIndex(row<span class="operator">,</span> column<span class="operator">,</span> childItem);
      <span class="keyword">else</span>
          <span class="keyword">return</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span>();
  }

  <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> TreeModel<span class="operator">::</span>parent(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>index) <span class="keyword">const</span>
  {
      <span class="keyword">if</span> (<span class="operator">!</span>index<span class="operator">.</span>isValid())
          <span class="keyword">return</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span>();

      TreeItem <span class="operator">*</span>childItem <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator">&lt;</span>TreeItem<span class="operator">*</span><span class="operator">&gt;</span>(index<span class="operator">.</span>internalPointer());
      TreeItem <span class="operator">*</span>parentItem <span class="operator">=</span> childItem<span class="operator">-</span><span class="operator">&gt;</span>parentItem();

      <span class="keyword">if</span> (parentItem <span class="operator">=</span><span class="operator">=</span> rootItem)
          <span class="keyword">return</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span>();

      <span class="keyword">return</span> createIndex(parentItem<span class="operator">-</span><span class="operator">&gt;</span>row()<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> parentItem);
  }

  <span class="type">int</span> TreeModel<span class="operator">::</span>rowCount(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qmodelindex.html">QModelIndex</a></span> <span class="operator">&amp;</span>parent) <span class="keyword">const</span>
  {
      TreeItem <span class="operator">*</span>parentItem;
      <span class="keyword">if</span> (parent<span class="operator">.</span>column() <span class="operator">&gt;</span> <span class="number">0</span>)
          <span class="keyword">return</span> <span class="number">0</span>;

      <span class="keyword">if</span> (<span class="operator">!</span>parent<span class="operator">.</span>isValid())
          parentItem <span class="operator">=</span> rootItem;
      <span class="keyword">else</span>
          parentItem <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator">&lt;</span>TreeItem<span class="operator">*</span><span class="operator">&gt;</span>(parent<span class="operator">.</span>internalPointer());

      <span class="keyword">return</span> parentItem<span class="operator">-</span><span class="operator">&gt;</span>childCount();
  }

  <span class="type">void</span> TreeModel<span class="operator">::</span>setupModelData(<span class="keyword">const</span> <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> <span class="operator">&amp;</span>lines<span class="operator">,</span> TreeItem <span class="operator">*</span>parent)
  {
      <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator">&lt;</span>TreeItem<span class="operator">*</span><span class="operator">&gt;</span> parents;
      <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator">&lt;</span><span class="type">int</span><span class="operator">&gt;</span> indentations;
      parents <span class="operator">&lt;</span><span class="operator">&lt;</span> parent;
      indentations <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="number">0</span>;

      <span class="type">int</span> number <span class="operator">=</span> <span class="number">0</span>;

      <span class="keyword">while</span> (number <span class="operator">&lt;</span> lines<span class="operator">.</span>count()) {
          <span class="type">int</span> position <span class="operator">=</span> <span class="number">0</span>;
          <span class="keyword">while</span> (position <span class="operator">&lt;</span> lines<span class="operator">[</span>number<span class="operator">]</span><span class="operator">.</span>length()) {
              <span class="keyword">if</span> (lines<span class="operator">[</span>number<span class="operator">]</span><span class="operator">.</span>at(position) <span class="operator">!</span><span class="operator">=</span> <span class="char">' '</span>)
                  <span class="keyword">break</span>;
              position<span class="operator">+</span><span class="operator">+</span>;
          }

          <span class="type"><a href="../qtcore/qstring.html">QString</a></span> lineData <span class="operator">=</span> lines<span class="operator">[</span>number<span class="operator">]</span><span class="operator">.</span>mid(position)<span class="operator">.</span>trimmed();

          <span class="keyword">if</span> (<span class="operator">!</span>lineData<span class="operator">.</span>isEmpty()) {
              <span class="comment">// Read the column data from the rest of the line.</span>
              <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> columnStrings <span class="operator">=</span> lineData<span class="operator">.</span>split(<span class="string">&quot;\t&quot;</span><span class="operator">,</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span><span class="operator">::</span>SkipEmptyParts);
              <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator">&lt;</span><span class="type"><a href="../qtcore/qvariant.html">QVariant</a></span><span class="operator">&gt;</span> columnData;
              <span class="keyword">for</span> (<span class="type">int</span> column <span class="operator">=</span> <span class="number">0</span>; column <span class="operator">&lt;</span> columnStrings<span class="operator">.</span>count(); <span class="operator">+</span><span class="operator">+</span>column)
                  columnData <span class="operator">&lt;</span><span class="operator">&lt;</span> columnStrings<span class="operator">[</span>column<span class="operator">]</span>;

              <span class="keyword">if</span> (position <span class="operator">&gt;</span> indentations<span class="operator">.</span>last()) {
                  <span class="comment">// The last child of the current parent is now the new parent</span>
                  <span class="comment">// unless the current parent has no children.</span>

                  <span class="keyword">if</span> (parents<span class="operator">.</span>last()<span class="operator">-</span><span class="operator">&gt;</span>childCount() <span class="operator">&gt;</span> <span class="number">0</span>) {
                      parents <span class="operator">&lt;</span><span class="operator">&lt;</span> parents<span class="operator">.</span>last()<span class="operator">-</span><span class="operator">&gt;</span>child(parents<span class="operator">.</span>last()<span class="operator">-</span><span class="operator">&gt;</span>childCount()<span class="operator">-</span><span class="number">1</span>);
                      indentations <span class="operator">&lt;</span><span class="operator">&lt;</span> position;
                  }
              } <span class="keyword">else</span> {
                  <span class="keyword">while</span> (position <span class="operator">&lt;</span> indentations<span class="operator">.</span>last() <span class="operator">&amp;</span><span class="operator">&amp;</span> parents<span class="operator">.</span>count() <span class="operator">&gt;</span> <span class="number">0</span>) {
                      parents<span class="operator">.</span>pop_back();
                      indentations<span class="operator">.</span>pop_back();
                  }
              }

              <span class="comment">// Append a new item to the current parent's list of children.</span>
              parents<span class="operator">.</span>last()<span class="operator">-</span><span class="operator">&gt;</span>appendChild(<span class="keyword">new</span> TreeItem(columnData<span class="operator">,</span> parents<span class="operator">.</span>last()));
          }

          <span class="operator">+</span><span class="operator">+</span>number;
      }
  }

</pre>
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<!-- @@@itemviews/simpletreemodel/treemodel.cpp -->
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